A method and system for commercial and industrial energy storage control based on reverse flow and demand

Abstract

The application discloses a commercial and industrial energy storage control method and system based on reverse flow and demand, wherein the method comprises the following steps: collecting operation data of commercial and industrial energy storage and a power grid, and obtaining planning data from an energy management system; judging whether a battery management system is faulty based on the operation data, and setting the charging and discharging power to zero and cutting into a safe shutdown mode if there is a fault; judging whether there is reverse flow or demand overrun, cutting into a reverse flow charging mode if there is reverse flow, and adjusting the discharging power in real time; cutting into a demand discharging mode if there is demand overrun, and adjusting the discharging power in real time; and cutting into a planning mode if the battery management system is not faulty, there is no reverse flow, and there is no demand overrun, and obtaining the charging and discharging power based on the planning data and performing. The operation mode is switched according to the priority of instant data, so that the system safety of commercial and industrial energy storage is ensured under complex working conditions, a certain economy is ensured, and the coordinated control of the energy storage system is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of energy storage, in particular to a commercial and industrial energy storage control method and system based on reverse flow and demand. BACKGROUND

[0002] The commercial and industrial energy storage system is a set of energy storage equipment designed for commercial and industrial users, which usually includes a battery pack, a power conversion system (PCS), a battery management system (BMS), and a monitoring platform. It can connect to user's deep load, distributed photovoltaic, wind turbine, and main grid to realize flexible energy scheduling for charging and discharging. The commercial and industrial energy storage system can balance the power load, improve energy utilization efficiency, reduce power cost and energy risk, and achieve peak load shifting, standby energy, and auxiliary renewable energy generation stability.

[0003] The existing commercial and industrial energy storage system usually has a single control strategy, which has obvious defects, including: logic conflict, when the demand is about to exceed the limit, if reverse flow occurs, the single strategy is easy to trigger the reverse flow prevention mechanism and issue a charging instruction, which exacerbates the demand exceeding the limit; control rigidity, most systems usually use fixed threshold or simple start-stop control, which cannot adaptively calculate according to real-time power difference, BMS limit and preset value, resulting in insufficient control accuracy, low economic efficiency and even reduced battery life; lack of system coordination, the BMS limit instruction, inverter planning instruction and real-time demand of the main grid lack coordinated scheduling, and the final scheduling is not a global optimal solution; and only according to individual elements to issue instructions in complex conditions, which causes new demand exceeding the limit or reverse flow problems, lack of verification and constraints. SUMMARY

[0004] The present application mainly provides a commercial and industrial energy storage control method based on reverse flow and demand to solve the problem of insufficient precision and lack of coordination in the existing commercial and industrial energy storage system.

[0005] To solve the above technical problems, one technical solution adopted by the present application is to provide a commercial and industrial energy storage control method based on reverse flow and demand, comprising the steps of:

[0006] S10: Real-time acquisition of operation data of commercial and industrial energy storage and power grid, and acquisition of planning data from an energy management system;

[0007] S20: Based on the operation data, determining whether the battery management system is faulty, if there is a fault, cutting into a safe shutdown mode and setting the charging and discharging power to zero, if not, continuing the subsequent steps;

[0008] S30: judging whether there is reverse flow or demand overrun based on the operation data, if there is reverse flow, cutting into reverse flow charging mode, and adjusting discharging power in real time based on the planning data and the operation data; if there is demand overrun, cutting into demand discharging mode, and adjusting discharging power in real time based on the planning data and the operation data; if not, continuing the subsequent steps;

[0009] S40: if there is no fault of the battery management system, no reverse flow, and no demand overrun, cutting into the planning mode and obtaining charging and discharging power based on the planning data;

[0010] S50: the industrial and commercial energy storage performs charging and discharging actions based on the charging and discharging power.

[0011] In a possible implementation, the operation data includes grid-connected point power, planning power, real-time state of charge of the battery, battery temperature, and battery health status, and the planning data includes planning power and demand limit value.

[0012] In a possible implementation, the step of judging whether the battery management system is faulty based on the operation data, if there is fault, cutting into the safe shutdown mode and setting the charging and discharging power to zero, if not, continuing the subsequent steps, includes:

[0013] S21: obtaining the maximum allowed power of the battery management system based on the operation data, and judging that the battery management system has a serious fault when the maximum allowed power is zero, and stopping all charging and discharging instructions.

[0014] In a possible implementation, the step of judging whether there is reverse flow or demand overrun based on the operation data, if there is reverse flow, cutting into reverse flow charging mode, and adjusting discharging power in real time based on the planning data and the operation data, if not, continuing the subsequent steps, includes:

[0015] S31: the reverse flow charging mode is that obtaining an absolute value of reverse flow power based on the operation data, when the planning power and the absolute value of the reverse flow power are both less than the maximum power of the battery management system, taking the minimum value of the planning power and the absolute value of the reverse flow power as the charging power, otherwise, taking the maximum power of the battery management system as the charging power.

[0016] In a possible implementation, the step of if there is demand overrun, cutting into demand discharging mode, and adjusting discharging power in real time based on the planning data and the operation data, if not, continuing the subsequent steps, includes:

[0017] S32: the demand discharging mode is that obtaining demand overrun power based on the operation data, when the planning power and the demand overrun power are both less than the maximum power of the battery management system, taking the minimum value of the planning power and the demand overrun power as the discharging power, otherwise, taking the maximum power of the battery management system as the discharging power.

[0018] In a possible implementation, the step of performing the charging and discharging action by the industrial and commercial energy storage based on the charging and discharging power comprises:

[0019] S60: obtaining the total load power and the distributed power, combining the charging and discharging power, judging whether the current charging and discharging action triggers the demand excess or causes the reverse flow, and performing the constraint on the charging and discharging power based on the judgment result.

[0020] In a possible implementation, the step of performing the charging and discharging action by the industrial and commercial energy storage based on the charging and discharging power comprises:

[0021] S51: obtaining the daily basic charging and discharging power interval based on the system mode, the historical load, the time-of-use price and the output prediction;

[0022] S52: obtaining the demand period energy cumulative value and the energy warning threshold, combining the basic charging and discharging power interval, and obtaining the minute-level reference power;

[0023] S53: obtaining the instant charging and discharging power based on the control mode, the daily basic charging and discharging power interval and the minute-level reference power.

[0024] In a possible implementation, the step of obtaining the charging and discharging power based on the control mode, the daily basic charging and discharging power interval and the minute-level reference power comprises:

[0025] S54: obtaining the remaining energy overrun based on the demand and the initial charging and discharging power in one period, and correcting the charging and discharging power based on the judgment result of the overrun risk;

[0026] S55: constructing a system power balance model, judging whether the initial charging and discharging power causes the reverse flow or the demand excess, and correcting the initial charging and discharging power based on the judgment result.

[0027] In a possible implementation, the step of performing the charging and discharging action by the industrial and commercial energy storage based on the charging and discharging power further comprises:

[0028] S56: performing the charging and discharging action by the energy storage converter based on the charging and discharging power, and returning to step S10 after one adjustment period to enter the next adjustment period.

[0029] To solve the above technical problems, another technical solution adopted by the present application is to provide an industrial and commercial energy storage control system based on reverse flow and demand, which is suitable for performing an industrial and commercial energy storage control method based on reverse flow and demand as described above, comprising:

[0030] The collection module is used for collecting operation data of industrial and commercial energy storage and a power grid in real time and obtaining plan data from an energy management system;

[0031] The first analysis module is used for judging whether the battery management system is faulty based on the operation data, and if there is a fault, the safe shutdown mode is switched in and the charging and discharging power is set to zero, and if not, the subsequent step is continued.

[0032] The second analysis module is used for judging whether there is reverse flow or demand overrun based on the operation data, and if there is reverse flow, the reverse flow charging mode is switched in, and the discharging power is adjusted in real time based on the plan data and the operation data, and if there is demand overrun, the demand discharging mode is switched in, and the discharging power is adjusted in real time based on the plan data and the operation data, and if not, the subsequent step is continued.

[0033] The third analysis module is used for switching in the plan mode and obtaining the charging and discharging power based on the plan data if the battery management system is not faulty, there is no reverse flow, and there is no demand overrun.

[0034] The execution module is used for the industrial and commercial energy storage to perform the charging and discharging action based on the charging and discharging power.

[0035] The beneficial effects of the present application are that, unlike the prior art, the present application discloses an industrial and commercial energy storage control method and system based on reverse flow and demand, which switches the operation mode strictly according to the priority to ensure the system safety of the industrial and commercial energy storage under complex working conditions, ensures a certain economy, and realizes the coordinated control of the energy storage system. BRIEF DESCRIPTION OF DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained without creative labor on the basis of these drawings.

[0037] Figure 1 is a structural schematic diagram of the first embodiment of the present application. DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0039] The terms "first", "second", "third", etc., in the embodiments of the present application are used only for descriptive purposes and cannot be understood as indicating or implying relative importance or implying that the indicated technical features are limited to a certain number. Thus, the features defined with "first", "second", "third" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise explicitly and specifically limited. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units is not limited to the listed steps or units, but can optionally include steps or units not listed, or can optionally include other steps or units inherent to the process, method, product or device.

[0040] Reference herein to "embodiments" means that a particular feature, structure, or characteristic described in connection with an embodiment can be included in at least one embodiment of the application. The appearance of the phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily mutually exclusive of other embodiments. It is explicitly and implicitly understood that the embodiments described herein can be combined with other embodiments.

[0041] Please refer to Figure 1 The embodiments of the present application include a commercial and industrial energy storage control method based on reverse flow and demand, comprising the steps of:

[0042] S10: Real-time acquisition of operation data of commercial and industrial energy storage and power grid, and acquisition of planning data from energy management system (EMS);

[0043] S20: Based on the operation data, it is judged whether the battery management system (BMS) is faulty. If there is a fault, the safe shutdown mode is switched in and the charge and discharge power is set to zero. If not, the subsequent steps are continued;

[0044] S30: Based on the operation data, it is judged whether there is reverse flow or demand overrun. If there is reverse flow, the reverse flow charging mode is switched in, and the discharge power is adjusted in real time based on the planning data and operation data. If there is demand overrun, the demand discharge mode is switched in, and the discharge power is adjusted in real time based on the planning data and operation data. If not, the subsequent steps are continued;

[0045] S40: If the battery management system has no fault, no reverse flow, and no demand overrun, the planning mode is switched in and the charge and discharge power is obtained based on the planning data;

[0046] S50: The commercial and industrial energy storage performs charge and discharge actions based on the charge and discharge power.

[0047] Specifically, the collection of each data is performed in step S10, including running data and planning data, wherein the running data includes grid-connected point power P n , BMS maximum allowable power P b , demand period energy cumulative value E a , total load power P l , local power generation output power P s , and the planning data includes planned power P p , user and grid agreed demand limit value D l .

[0048] The BMS maximum allowable power P b is obtained by detecting voltage limit power P v , temperature limit power P t , SOC limit power P soc , SOH limit power P soh , and selecting the minimum value as the BMS maximum allowable power, so as to ensure that the maximum allowable power does not exceed any limit power and ensure system safety.

[0049] Further, the collection frequency of each data can be set differently according to the type of data. High-frequency data such as grid-connected point power P n , total load power P l , and local power generation output power P s may be collected at a frequency of 10 kHz; medium-frequency data such as BMS maximum allowable power P b and demand period energy cumulative value E a may be collected at a frequency of 1 Hz; and low-frequency data such as planned power P p and user and grid agreed demand limit value D l may be collected at a frequency of once every 10 minutes.

[0050] In step S20, it is judged whether the battery management system BMS is in failure according to the BMS maximum allowable power P b . When the BMS maximum allowable power P b is zero, it indicates that the voltage limit power P v , temperature limit power P t , SOC limit power P soc , and SOH limit power P soh are all zero, at this time the energy storage system is switched into a safe shutdown mode and the charging and discharging are stopped. The priority of step S20 is the highest, that is, as soon as it is found that the battery management system BMS is in failure at any time, the safe shutdown mode is entered to avoid the continuous existence of the failure leading to problem escalation and causing more serious consequences.

[0051] When detecting no fault of the BMS in step S30, the grid-connected point power P n The current state is determined, and the grid-connected point power P n is positive, indicating that the energy storage system takes power from the grid, and the grid-connected point power P n is negative, indicating that the system feeds power to the grid, so the grid-connected point power P n is detected to determine the current state of the system, that is, when the detected value of the grid-connected point power P n is negative, it is determined that reverse flow occurs, and the energy storage system is switched to the reverse flow charging mode, and the system charges the excess energy to the energy storage device to absorb the reverse flow power and avoid grid penalties. When the detected value of the grid-connected point power P n exceeds the demand limit value D l , it is determined that the current demand exceeds the limit, and the energy storage system is switched to the demand discharging mode, and the system reduces the excess demand power to control the demand cost.

[0052] In step S40, if the current grid-connected point power P n does not meet the requirements of the two modes in step S30, that is, 0≤P n ≤D l , it is determined that the battery management system has no fault, the system has no reverse flow, and the demand does not exceed the limit, and the system is switched to the planning mode at this time to obtain and execute the planned power P p to improve the economy of the energy storage system.

[0053] In step S50, the industrial and commercial energy storage system executes the charging and discharging power corresponding to the state selected according to the foregoing steps S20-S40 to improve the economy of the energy storage system under the premise of priority to ensure safety.

[0054] The industrial and commercial energy storage control method based on reverse flow and demand in the embodiment is for the operation control of the industrial and commercial energy storage system, and strictly switches the operation mode according to the priority to ensure the safety of the industrial and commercial energy storage system under complex working conditions, while ensuring a certain economy, and realizes the coordinated control of the system.

[0055] In an embodiment, the operation data includes the grid-connected point power, the planned power, the real-time state of charge of the battery, the battery temperature, and the battery health state, and the planning data includes the preset demand limit value and the planned power.

[0056] The real-time state of charge of the battery is the battery SOC, and the battery health state is the battery SOH. The battery SOC, the battery SOH, the battery temperature, and the voltage limit power are combined to obtain the maximum allowable power of the BMS, that is, the voltage limit power P v , the temperature limit power P t , the SOC limit power P soc , and the SOH limit power Psoh And select the minimum value as the maximum allowable power P of the BMS. b The maximum permissible power of the BMS obtained in this way can be ensured not to exceed any power limit, so as to ensure the safety of the energy storage system as much as possible.

[0057] In one embodiment, based on operational data, it is determined whether the battery management system is faulty. If a fault exists, a safety shutdown mode is entered and the charging and discharging power is set to zero. Otherwise, subsequent steps are continued, including:

[0058] S21: Obtain the maximum allowable power of the battery management system based on the operating data. When the maximum allowable power is zero, it is determined that there is a serious fault in the battery management system, and all charging and discharging commands are stopped.

[0059] Specifically, the maximum allowable power P of the BMS b The power can be obtained through various power limits, including voltage-limited power P. v Temperature-limited power P t SOC power limit P soc SOH limiting power P soh The minimum value is selected as the maximum allowable power of the BMS. Since the maximum allowable power does not exceed any limit power, the system safety can be ensured to the greatest extent.

[0060] In one embodiment, based on operational data, it is determined whether there is reverse current or excessive demand. If reverse current exists, the reverse current charging mode is switched on. The step of adjusting the discharge power in real time based on planned data and operational data includes:

[0061] S31: In reverse charging mode, the absolute value of reverse power is obtained based on the operating data. When both the planned power and the absolute value of reverse power are less than the maximum power of the battery management system, the minimum value between the planned power and the absolute value of reverse power is taken as the charging power; otherwise, the maximum power of the battery management system is taken as the charging power.

[0062] Specifically, the absolute value of the countercurrent power P r Take the grid connection point power P n The absolute value of P r =|P n | Then, the absolute value of the reverse power P r With BMS maximum allowable power P b Planned power P p The comparison is as follows:

[0063] If (P) p <P b &&P r <P b ),

[0064] P = min(P)n , P p ),

[0065] else P c =P b ,

[0066] i.e. when the planned power P p is less than the BMS maximum allowed power P b and the absolute value of the reverse power P r is less than the BMS maximum power, the charging power P c takes the minimum of the grid-connected point power P n and the planned power P p , otherwise the BMS maximum allowed power P b is taken as the charging power. This logic ensures that the reverse power can be completely absorbed, and the safety limit of the BMS will not be exceeded, effectively ensuring the safety performance of the energy storage system.

[0067] In an embodiment, if the demand exceeds the limit, the demand discharging mode is switched in, and the discharging power is adjusted in real time based on the planned data and the operating data, otherwise the subsequent steps are continued, including:

[0068] S32: The demand discharging mode is to obtain the demand excess power based on the operating data, when the planned power and the demand excess power are both less than the maximum power of the battery management system, the minimum of the planned power and the demand excess power is taken as the discharging power, otherwise the maximum power of the battery management system is taken as the discharging power.

[0069] Specifically, the demand excess power D o takes the difference between the grid-connected point power P n and the demand limit value D l , i.e.:

[0070] D o =P n -D l ,

[0071] And then compared with the planned power P p and the BMS maximum allowed power P b :

[0072] If (P p <P b && D o <P b ),

[0073] P = min (D o , P p ),

[0074] else P d =P b ,

[0075] i.e. when the planned power P p is less than the BMS maximum allowed power P b and the excess demand power D o is less than the BMS maximum allowed power P b , the discharge power P d is taken as the minimum of the excess demand power D o and the planned power P p , and if the condition is not met, the BMS maximum allowed power P b is taken as the discharge power. Under this logic, while the excess demand power is reduced, the demand cost is controlled, and the economic efficiency of the energy storage system is effectively improved.

[0076] In an embodiment, after the step of performing the charging and discharging action based on the charging and discharging power by the industrial and commercial energy storage, the method comprises:

[0077] S60: obtaining the total load power and the distributed power, combining the charging and discharging power, judging whether the current charging and discharging action triggers the excess demand or causes the reverse flow, and based on the judgment result, the charging and discharging power is constrained.

[0078] After the judgment in the foregoing step, according to the charging and discharging power of the charging and discharging instruction issued by the reverse flow charging mode, the excess demand discharging mode or the planned mode, it is judged whether the charging and discharging with this power will cause the excess demand or the reverse flow. Specifically, the system total power balance model is constructed:

[0079] P n = P l + P c - P s - P d ,

[0080] wherein P n is the grid-connected point power, P s is the local power output, P l is the total load power, P c is the charging power, and P d is the discharging power. The total power balance model is used to guide and correct the constraint of the charging and discharging power.

[0081] When in the reverse flow charging mode, i.e. the current charging power P c > 0, it is judged in real time whether the sum of the charging and discharging power and the load power will cause the grid power to exceed the demand limit, i.e. whether there is:

[0082] P c + P l > D l ,

[0083] If the above formula is established, it means that the current charging power may cause demand overrun, and the energy storage system should reduce the charging power, and the corrected charging power P c is:

[0084] P c =D l -P l ,

[0085] When P l >D l , the result of P c is negative, that is, at this time the charging should be stopped and converted to discharging, and the discharging power P d =-P c .

[0086] When in demand discharging mode, that is, P d >0, at this time it needs to be judged whether the sum of local power output power P s and discharging power P d exceeds the total load power, thereby causing reverse flow, that is, whether the following formula is established:

[0087] P d +P s >P l ,

[0088] If it is established, it means that the current discharging power may cause reverse flow, so the energy storage system should reduce the discharging power, and the corrected discharging power P d is:

[0089] P d =P l -P s ,

[0090] When P s >P l , the result of discharging power P d is negative, that is, at this time the discharging should be stopped and converted to charging action to consume excess energy, and the charging power P c =-P d .

[0091] Based on power balance, the charging and discharging power is constrained to avoid new reverse flow or demand overrun caused by charging and discharging adjustment, thereby ensuring the control accuracy of the energy storage system and improving safety and economy.

[0092] In an embodiment, the step of the industrial and commercial energy storage system performing charging and discharging action based on charging and discharging power includes:

[0093] S51: Based on system mode, historical load, time-of-use price, and output prediction, obtain daily basic charging and discharging power range;

[0094] S52: Obtain the energy cumulative value of the demand period, the energy warning threshold, and the minute-level reference power by combining the basic charging and discharging power interval;

[0095] S53: Obtain the instant charging and discharging power based on the control mode, the daily basic charging and discharging power interval, and the minute-level reference power.

[0096] Specifically, in step S51, the interval value of the charging and discharging power in units of days is determined to determine the basic range of the day and perform primary constraint.

[0097] Based on the next-day time-of-use price, the past 72 hours of historical load, and the output prediction value of the local power generation device in the system, the 24 hours are divided into a valley period and a peak period. In the valley period, the maximum charging is targeted, and in the peak period, the maximum discharging is targeted.

[0098] In this embodiment, the price lower than 1 yuan / d is the valley period, the upper limit value of the charging interval in the valley period is min[battery rated power, transformer capacity-historical load minimum value in the same period], and the lower limit value is 60% of the upper limit value. The price higher than 1 yuan / d is the peak period, and the upper limit value of the discharging interval in the peak period is min[battery rated power, historical load maximum load in the same period], and the lower limit value is 50% of the upper limit value.

[0099] If there is a local power generation device (such as a photovoltaic or wind turbine), the output prediction of the next day can be obtained from the local power generation device to correct the charging and discharging power interval. The specific obtaining method can be to estimate according to the historical output power of the local power generation device, or to directly obtain the planned output scheme. After obtaining the next-day output prediction data, the predicted maximum output P x and the minimum output P y , the charging interval is corrected to: charging interval lower limit = original lower limit + 0.8*P y , and the discharging interval upper limit = original upper limit + 0.3*P x .

[0100] In step S52, the energy cumulative value E a of the demand period and the energy warning threshold E w are obtained, and the minute-level reference power is obtained by combining the daily basic charging and discharging power interval obtained in step S51. In this embodiment, the energy cumulative value E a of the demand period is first judged. If E a E w , that is, the energy cumulative value of the demand period does not reach the warning, the median value of the daily basic charging and discharging power interval is directly taken as the reference power P0; if E a ≥E wIf the cumulative value of the demand period energy reaches the early warning, the minute-level reference power P0 is corrected based on the remaining time and the remaining energy of the current period:

[0101] ,

[0102] Wherein, T is the demand period time, 15 minutes in the embodiment, T k is the period time that has been running at this time, the difference between the two (i.e. the denominator) is the remaining time of the current period, D l is the demand limit value agreed by the user and the power grid. The minute-level reference power P0 is taken as the basic value to guide the power control of the corresponding time node.

[0103] In step S53, the instantaneous charging and discharging power is obtained according to the system mode (safety shutdown mode, reverse flow charging mode, demand discharging mode or planning mode) determined in the foregoing steps and the reference power.

[0104] The instantaneous charging and discharging power in the embodiment is adjusted in millisecond level, and other time units less than minute can also be taken in other embodiments.

[0105] If in the reverse flow charging mode, the instantaneous charging power P ck is:

[0106] P ck =min (P p , P0, P b , P r ),

[0107] Wherein, P p is the planning power, P0 is the minute-level reference power, P b is the maximum allowed power of BMS, P r is the absolute value of reverse flow power, and the instantaneous charging power P ck takes the minimum value to realize the priority consumption of reverse flow power and ensure that the charging power does not exceed the BMS limit and the reference power.

[0108] If in the demand discharging mode, the instantaneous discharging power P dk is:

[0109] P dk =min (P p , P0, P b , D o ),

[0110] Wherein, P p is the planning power, P0 is the minute-level reference power, P b is the maximum allowed power of BMS, and D o is the demand excess power, and the instantaneous discharging power Pdk Take the minimum value to achieve priority reduction of excess power demand while ensuring that the discharge power does not exceed the limit of the BMS and the reference power.

[0111] If in the planning mode, the initial power P k is:

[0112] P k = min (P p , P0, P b ),

[0113] That is, according to the plan of the energy management system EMS, while keeping the reference power and the limit of the battery management system BMS.

[0114] According to the processing of steps S51 to S53, the initial charge and discharge power is corrected to ensure the safety of the energy storage system and no compliance risk.

[0115] In an embodiment, after the step of obtaining the charge and discharge power based on the control mode, the daily basic charge and discharge power interval, and the minute-level reference power, the step includes:

[0116] S54: Based on the demand and the initial charge and discharge power in a period, obtain the remaining energy over-limit, and correct the charge and discharge power based on the judgment result of the over-limit risk;

[0117] S55: Construct a system power balance model to determine whether the initial charge and discharge power leads to reverse flow or excess demand, and correct the initial charge and discharge power based on the judgment result.

[0118] Specifically, in step S54, the energy over-limit risk in the demand period is judged, and for all operating modes, the initial charge and discharge power P k , the demand period energy cumulative value E a , the energy warning threshold E w , the time T of the demand period, the remaining time energy E p in the period is predicted:

[0119] E p = E a + P k * (T-T k ),

[0120] Where T k is the running time at this time in the period, the obtained remaining time energy E p in the period is compared with the predicted energy over-limit value D l *T, if there is:

[0121] E p > D l *T,

[0122] If the energy prediction value of the remaining time in the cycle is out of limit, the charging and discharging power is corrected, and the corrected charging and discharging power P kc is:

[0123] ,

[0124] If E p ≤D l *T is true, i.e. the energy prediction value of the remaining time in the cycle will not cause out of limit, the charging and discharging power P kc does not need to be corrected, and the charging and discharging power obtained in the foregoing steps is continued to be executed.

[0125] In step S55, based on the system total power balance model:

[0126] P n =P l +P c -P s -P d ,

[0127] For whether the initial power obtained in the foregoing steps can cause reverse flow or risk of excessive demand, the case is corrected again:

[0128] If in the reverse flow charging mode or the planning mode, it is judged whether:

[0129] P kc +P l >D l ,

[0130] is true, if true, it indicates that the corrected charging and discharging power will cause excessive demand, and then it is judged whether P l is greater than D l , if P l ≤D l , the charging action is maintained and the final charging power P cf：

[0131] P cf =D l -P l ;

[0132] If P l >D l , the charging action is stopped, converted to discharging, and the final discharging power P df :

[0133] P df =P l -D l .

[0134] If in the demand discharge mode or the planning mode, it is determined whether the following condition is met:

[0135] P kc +P s >P l ,

[0136] If the condition is met, it indicates that the corrected charge and discharge power will cause a reverse flow. Then, according to the size relationship between P s and P l , the following processing is performed. If P s ≤ P l , the discharge operation is maintained, and the final discharge power P df is as follows:

[0137] P df = P l -P s ,

[0138] If P s >P l , the discharge operation is stopped, the charge operation is started, and the final charge power P cf is as follows:

[0139] P cf = P s -P l .

[0140] The final charge and discharge power is taken as the final output, which ensures safety and prevents over-regulation from causing demand overage or reverse flow again, thereby improving the safety and stability of the system.

[0141] In an embodiment, the step of performing the charge and discharge operation by the industrial and commercial energy storage based on the charge and discharge power further includes:

[0142] S56: The energy storage inverter performs the charge and discharge operation based on the charge and discharge power, and returns to step S10 after an adjustment period to enter the next adjustment period.

[0143] Specifically, the length of the adjustment period can be set according to hardware performance (such as chip computing power) and combined with the data acquisition frequency to balance the operation speed and adjustment accuracy. The shorter the adjustment period, the higher the adjustment frequency and the higher the adjustment accuracy. The longer the adjustment period, the lower the demand for hardware performance, which can reduce the cost of the energy storage system. In this embodiment, the length of one adjustment period is 1 second. After each period is completed, it returns to S10 to enter the next adjustment period, thereby realizing stable and long-term control and adjustment of the energy storage system.

[0144] The above is the explanation of the industrial and commercial energy storage control method based on reverse flow and demand in the embodiments of the present application. The industrial and commercial energy storage control system based on reverse flow and demand in the embodiments of the present application is described below. The industrial and commercial energy storage control system based on reverse flow and demand is suitable for executing the industrial and commercial energy storage control method based on reverse flow and demand described above, and comprises:

[0145] The acquisition module is configured to acquire the operation data of the industrial and commercial energy storage and the power grid in real time, and obtain the planning data from the energy management system.

[0146] The first analysis module is configured to determine whether the battery management system is faulty based on the operation data, and if so, cut into the safe shutdown mode and set the charging and discharging power to zero, and if not, continue the subsequent steps.

[0147] The second analysis module is configured to determine whether there is reverse flow or demand overrun based on the operation data, and if so, cut into the reverse flow charging mode and adjust the discharging power in real time based on the planning data and the operation data, and if not, cut into the demand discharging mode and adjust the discharging power in real time based on the planning data and the operation data, and if not, continue the subsequent steps.

[0148] The third analysis module is configured to cut into the planning mode and obtain the charging and discharging power based on the planning data if the battery management system is not faulty, there is no reverse flow, and there is no demand overrun.

[0149] The execution module is configured to execute the charging and discharging action based on the charging and discharging power.

[0150] The above is only an embodiment of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation based on the content of the specification and drawings, or direct or indirect application in other related technical fields, is also included in the patent protection scope of the present application.

Claims

1. A reverse flow and demand based industrial and commercial energy storage control method, characterized by, The method comprises the steps of: S10: collecting operation data of industrial and commercial energy storage and power grid in real time, and obtaining planning data from an energy management system; S20: determining whether the battery management system is faulty based on the operation data, if there is a fault, cutting into a safe shutdown mode and setting the charging and discharging power to zero, if not, continuing the subsequent steps; S30: determining whether there is reverse flow or demand overrun based on the operation data, if there is reverse flow, cutting into a reverse flow charging mode, adjusting the charging power in real time based on the planning data and the operation data; if there is demand overrun, cutting into a demand discharging mode, adjusting the discharging power in real time based on the planning data and the operation data, if not, continuing the subsequent steps; S40: if the battery management system has no fault, no reverse flow and no demand overrun, cutting into a planning mode and obtaining the charging and discharging power based on the planning data; S50: the industrial and commercial energy storage performs charging and discharging actions based on the charging and discharging power; The step of determining whether there is reverse flow or demand overrun based on the operation data, if there is reverse flow, cutting into a reverse flow charging mode, adjusting the charging power in real time based on the planning data and the operation data, comprises: S31: the reverse flow charging mode is to obtain the absolute value of reverse flow power based on the operation data, when the planning power and the absolute value of reverse flow power are both less than the maximum power of the battery management system, taking the minimum value of the planning power and the absolute value of reverse flow power as the charging power, otherwise, taking the maximum power of the battery management system as the charging power; The step of if there is demand overrun, cutting into a demand discharging mode, adjusting the discharging power in real time based on the planning data and the operation data, if not, continuing the subsequent steps, comprises: S32: the demand discharging mode is to obtain the demand overrun power based on the operation data, when the planning power and the demand overrun power are both less than the maximum power of the battery management system, taking the minimum value of the planning power and the demand overrun power as the discharging power, otherwise, taking the maximum power of the battery management system as the discharging power.

2. A reverse flow and demand based industrial and commercial energy storage control method as claimed in claim 1 wherein, The operation data comprises grid-connected point power, planning power, battery real-time state of charge, battery temperature and battery health status, and the planning data comprises planning power and demand limit value.

3. A reverse flow and demand based industrial and commercial energy storage control method as claimed in claim 1, wherein, The step of determining whether the battery management system is faulty based on the operation data, if there is a fault, cutting into a safe shutdown mode and setting the charging and discharging power to zero, if not, continuing the subsequent steps, comprises: S21: obtaining the maximum allowable power of the battery management system based on the operation data, when the maximum allowable power is zero, determining that the battery management system has a serious fault, and stopping all charging and discharging instructions.

4. A reverse flow and demand based industrial and commercial energy storage control method as claimed in claim 1, wherein, After the step of the industrial and commercial energy storage performing charging and discharging actions based on the charging and discharging power, comprising: S60: obtaining total load power and distributed power supply power, combining the charging and discharging power, determining whether the current charging and discharging action triggers demand overrun or causes reverse flow, and constraining the charging and discharging power based on the determination result.

5. A reverse flow and demand based industrial and commercial energy storage control method as claimed in claim 1, wherein, The step of the industrial and commercial energy storage performing charging and discharging actions based on the charging and discharging power, comprising: S51: obtaining daily basic charging and discharging power interval based on system mode, historical load, time-of-use electricity price and output prediction; S52: Obtain the energy cumulative value of the demand period, the energy warning threshold, and the minute-level reference power based on the basic charging and discharging power interval; S53: Obtain the instant charging and discharging power based on the control mode, the daily basic charging and discharging power interval, and the minute-level reference power.

6. A reverse flow and demand based industrial and commercial energy storage control method as claimed in claim 5 wherein, After the step of obtaining the charging and discharging power based on the control mode, the daily basic charging and discharging power interval, and the minute-level reference power, the method comprises: S54: Obtain the excess energy based on the demand and the initial charging and discharging power in a period, and correct the charging and discharging power based on the judgment result of the excess risk; S55: Construct a system power balance model, judge whether the initial charging and discharging power leads to reverse flow or demand excess, and correct the initial charging and discharging power based on the judgment result.

7. A reverse flow and demand based industrial and commercial energy storage control method as claimed in claim 1, wherein, The step of the industrial and commercial energy storage performing charging and discharging actions based on the charging and discharging power further comprises: S56: The energy storage converter performs based on the charging and discharging power, and returns to step S10 after one adjustment period to enter the next adjustment period.

8. A reverse flow and demand based industrial and commercial energy storage control system adapted to perform a reverse flow and demand based industrial and commercial energy storage control method as claimed in any one of claims 1 to 7, characterized by, Comprise: The acquisition module is used for collecting the operation data of the industrial and commercial energy storage and the power grid in real time, and obtaining the planning data from the energy management system; The first analysis module judges whether the battery management system is faulty based on the operation data, and if there is a fault, it cuts into the safe shutdown mode and sets the charging and discharging power to zero, and if not, it continues the subsequent steps; The second analysis module judges whether there is reverse flow or demand excess based on the operation data, if there is reverse flow, it cuts into the reverse flow charging mode, and adjusts the charging power in real time based on the planning data and the operation data; if the demand is excessive, it cuts into the demand discharging mode, and adjusts the discharging power in real time based on the planning data and the operation data, if not, it continues the subsequent steps; the reverse flow charging mode is to obtain the absolute value of the reverse flow power based on the operation data, when the planned power and the absolute value of the reverse flow power are both less than the maximum power of the battery management system, the minimum value of the planned power and the absolute value of the reverse flow power is taken as the charging power, otherwise the maximum power of the battery management system is taken as the charging power; the demand discharging mode is to obtain the excess demand power based on the operation data, when the planned power and the excess demand power are both less than the maximum power of the battery management system, the minimum value of the planned power and the excess demand power is taken as the discharging power, otherwise the maximum power of the battery management system is taken as the discharging power; The third analysis module is used for cutting into the planning mode and obtaining the charging and discharging power based on the planning data if the battery management system has no fault, no reverse flow, and no demand excess; The execution module is used for the industrial and commercial energy storage to perform charging and discharging actions based on the charging and discharging power.

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